Drying apparatus.



R. GRAUER. DBYING APPARATUS. APPLIUATION FILED 311.14, 190e.

'rus Namzrs Psnsns ca.. wAsNlNmoN, D. c

R. GRAUER. DRYING APPARATUS.

Y fm/enfer: www @W www WW www a', wAsmNcroN. :1

ROBERT GRAUER, OF LOS ANGELES, CALIFORNIA.

DRYING APPARATUS.

Specification of Letters Patent.

Patented April 27, 1909.

Application led February 14, 1908. Serial No. 415,989.

To all 'whom it may concern:

Be ity known that I, ROBERT GRAUER, a subject of the Emperor ofAustria-Hungary, and a resident of Los Angeles, California, haveinvented new and useful Drying Apparatus, of which the following is aspecilication.

Objects of this invention are to provide a drier having improved meansfor advancing a suitably prepared moist material across a heated area ofair, and at the same time, agitate the material in such a manner as toac- Y celerate the drying thereof; to provide improved means forsupporting and progressively advancing said material during the dryingthereof vin such a manner as to allow the hot air to penetrate to everyportion of the material; to provide means adapted to operate upon thematerial to move it forward in the best manner when it is in the mostmoist condition, and in combination with said means, different meansbetter adapted to move the material forward after it has become partlydried; to provide improved means for removing and cleaning the .meansfor supporting the material; and to provide improved means forsupporting and confining the material in a manner allowing the heatedair to have' ready access therethrough.

f A further object is to provide a compact apparatus ywhereby thematerial will be compelled to move a long distance over the supportingmeans, and the said supporting means still be conned to a comparativelysmall compact case.

Another object of the invention is to provide improved means forautomatically advancing the material being operated upon, from oneseries of driers to another adjoining series of driers until thematerial is suf- 'liciently dried.

Other objects and advantages may hereinafter appear.

This drying apparatus is well adapted for drying fruit and othervegetable matter, and may also be used for drying other substances.

Referring to the accompanying drawings which illustrate the invention,Figure l is a longitudinal mid-section of a set of the driers. Fig. 2 isa plan view of the set of driers shown inl Fig. l, upper parts beingbroken away to show underlying parts, the line XM2 of Fig. l indicatingthe line of section. F'g. 3 is a cross-section of Figs. l and 2 on lineX-S thereof. Fig. 4 is an end elevation of one set of the ydryingelements. Fig. 5 is an enlarged plan section of a portion of one of thedrying troughs, showing, in addition to the trough, a fragment of thestirring means and of the heating means. Fig. 6 is a fra@- mentalelevation of a portion of the out-si e of the case, looking toward theleft of Fig. 5 and showing an end of one of the drying troughs. Fig. 7is a longitudinal section on line X-T of Fig. S, of a drying apparatuscomprising a' series of the driers illustrated in Figs. l to 4. Fig. Sis a plan of Fig. 7, the ventilators and top wall of the main case beingremoved.

Referring in detail to the drawings: 1 is a case or box forming a dryingchamber, wherein is mounted a series of superposed troughs 2, preferablyhaving curved or segmental bottoms with perforations 2a as best shown inFigs. 2 and 5. Said troughs are each provided with a screen orperforated cover 3 as best shown in Fig. 3 where 2b designates offsetlower edges of the covers for holding said covers in place. Said troughsare removablyvmounted in the easing 1, being desirably seated in seats 4at one end of the casing and extending outside the casing at the otherend through segmental grooves or openings 5. This construction makes itpossible to pull the troughs out from the left end of the case, as shownin Fig. l, for the purpose of cleaning the troughs to clear theperforations therethrough. The protruding ends of the troughs may eachbe provided with a flange 6 which thc operator may take hold of whenwithdrawing the trough. The covers 3 are desirably permanently fastenedwithin the case by any suitable means, said covers preferably formingarches over the tops of the troughs, thereby forming elongated chamberssu'l'liciently large to receive stirring and advancin(r :means whichwill hereinafter' be described.

Feeding means, desirably a feeding hopper 7, is provided on top of oneend of the case; said hopper discharging through a chute 8, into one ondof the initial or upper-most trough 2. ln said initial trough is mounteda spiral blade 9 on a shaft 10 extending 1ongitudinally of said uppertrough. Upon the shafts 10, 10, of the lower troughs are mountedspirally-arranged series of flattened stirring arms l1. Said flattenedstirring arms 11 are of such length that their outer ends move close tothe bottom of the trough when said shafts 10, l0 are rotated, each armbeing so inclined with relation to the rectly to the middle shaft 10.

length of the trough, as to move the material progressively forwardkalong its course when the shafts are rotated from right to left. At theend of the casing opposite'the hopper 7, the upper trough is providedwith a discharge opening 12 in its bottom, said opening dischargingthrough a chute 13, into the adjacent end of the next lower trough. VAtthe other end of said lower trough is a discharge opening 12 fordischarging into the lower trough shown in Fig. 1. Y

v14 designates a driving pulley fastened di- 1'5 is a cogwheel made fastto vthe said shaft 1() as shown in Fig. 1. 16, 16 are idle cog-wheelsmeshing respectively with the upper and lower sides of cog-wheel 15 andcommunicating motion from said cog-wheel. The idler 16 turns the uppercog-wheel 17 for driving upper shaft 10, and the idler 16 meshes Vithcog-wheel 17 for driving the lowermost shaft 10. 1t will be seen thatthis system of gearing for driving shafts 10, 1U and 10 will, ifl thestirring arms and the spiral blade are properly inclined with relationto the troughs,

feed the material in the upper trough from the right to the left side ofthe case, thence through discharge opening 12 back to the right side ofthe case through the middle chamber, thence through discharge opening 12bach to the left end of the case through the lower chamber. Said lowerchamber is provided at its left end with discharge opening"V 12 whichmay discharge material into another part of the drying apparatus, aswill be hereinafter described. The spiral blade 9 is adapted to receiveand positively move moist materialdirectly from the hopper and move saidmaterial on to the left end ofthe upper chamber, the 'current of Vhotair drying said material sufliciently by the time it reaches the leftend of the chamber and falls into the next lower chamber or tube so thatthe inclined stirring arms 11, although not soY positive in their actionwhen the material is in a wet or sticky state, may be safely relied uponto move the material further along its course after the material hasbecome somewhat dry in the elongated upper chamber.

The object of employing separate stirring arms, as shown in detail inFig. 5, instead of a continuous spiral blade, is to more effectuallyseparate and mix air with the particles of the material being dried asit progresses along the elongated lower chambers.

18 designates air dampers for admitting air to the bottom of the maindrying chamber 1. 19 designates Ya covered ventilator on top of thedrying chamber. Ventilator having desirably a damper 19 to regulate theescape of air and moisture therethrough.

20 designates piping containing steam 0r hot air supplied from anysuitable source (not shown) for heating the air vinside the dryingchamber, to cause the desired evaporation of moisture from the materialbeing dried.

A series of horizontally-arranged pipes 21 are desirably disposedparallel to and underneath each of the elongated drying chambers tocause a volume of heated air to pass directly up through the heatedperforated bottoms of said drying chambers.

21 are vertically-arranged pipes forming the necessary means forconducting air to one end of the horizontal series of pipes and 21 aresimilarly disposed :outlet pipes at the other 'end of said seriesofpipes. Near one I end of the main drying chamber is a horizontalcross-shaft 22, provided. near each side of the drier with one or morefans 23, the venes of which are so set as to create a circulation ofair, as indicated by the small arrows in Fig. 2. Near the other end ofthe drying chamber is a similar shaftv 24 having li-le fans 25 thereon.The longitudinal shaft 1() lof the drier is provided with a beveledceg-wheel 26 meshing with pinion bevel 27 on shaft128, `carrying apulley 29, and by means of belt 29 rotating pulley 24 to turn shaft 24.Shaft. 24 is provided at the other side of the case with a pulley 30 for'driving belt 31 thus t0 rotate pulley 82 and shaft 22, sothat all thefour fans 23 and 25 are thus rotated, causing a circulation of air asindicated by small arrows in Fig. 2. Shaft 22 carries pulley 33 fromwhich a belt 34 extends downward to a lower pulley 85 (see Fig. 4), thusto drive lower fan shafts 36 and 37 through a .pulley 38' and belt 3Q.rlhe driving connections last described serve to rotate the four lowerfans 40, to cause a circulation of air throughout the lower portion ofthe apparatus in a manner similar to that caused by the four upper fansalready described.

Flach series of elongated drying chambers may be provided with a feedingelevator 41 delivering into the hopper 7, and a discharge elevator 42 toreceive material in a more or less dry condition as delivered throughlower discharge openingf12 (see Fig. 1 for location of said dischargeopening). p

43 Vdesignates an inclined lower chute or trough for delivering thematerial from the lower elongated chamber, as shown in Fig. 3.

The left end of shaft 10 isprojectedoutsideof case 1 and .provided witha pulley 144 for driving belt 145 (see Figs. 1 and 2), said belt turningshaft 145 and thereby operating elevator 42 to raise the material`delivered through opening 12.

1n Figs. 7 and S, sets of superposed troughs 2 are shown arranged injuxtaposed series; said series being confined within a large box or case44, and'elevators 451and 46 lbeing used to transfer from one set ofdriers to the next set within 4the casing, while elevator 4Q is used todischarge to the outside of thecasing.

vWhen the apparatus is thus vassembled in juxtaposed series, the shaftof themiddle series may be provided at one end outside of the case, Withtwo belt pulleys over which pass the inner ends of belts 50 and 51. rPheouter end of belt`50 rotating shaft 52 and t ie outer end of belt 51rotating shaft 53; said. shaft 52 operates the interior mechanism of theright-hand series of drying apparatus shown in Figs. 7 and 8, inclosedin case 54 and the shaft 53 likewise operating the mechanism containedin the left-hand case The arrangement of spiral blades and stirring armsand of Wheels, shafts, etc. for driving them, is not explained in detailas to Figs. 7 and S, as such construction is merely a duplication ofthat already described and will be therefore readily understood, withoutfurther detailed description.

v Elevators 45, 46 and 49, as shown in Fig. 8, are driven by twistedbelts 45', 46 and 49,

in orderto givesaid elevators the proper direction of movement, ythearrangement of driving .means for elevators 45 and 49 being aduplication of the means illustrated in Figs. 7 and 8 for operatingelevator 46.

While the apparatus is well adapted for the dryinfr of fruit which hasbeen reviously sliced to the proper thinness, it is a so adapted to dryvarious other moist materials when reduced to a sufficient -lineness tobe handled by the conveying apparatus described. The stirring arms arenot arranged to form a spiral with a continuous edge, but, as clearlyshownin detail in Fig. 5, the ends of said arms are radially spacedapart so that as the material is operated upon, the particles thereofare separated from each other by adjacent arms and are therefore morethoroughly dried by the current of air circulated by the fans as alreadydescribed.

y The middle box 1 and also the boxes 54 and 55 at each side thereof,are provided. with perforated walls as shown where the Walls are. brokenaway and sectioned in Figs. 7 and 8, 60 indicating the perforationsthrough the walls in said views. The material being dried is movedprogressively through `the succession of boxes shown in Figs. 7 and 8,being first fed into the hopper 61 of box 54. Frein box 54 the materialis conveyed by elevator 45 to hopper 7 f* of box 1 a. From box 1 amaterial is elevated by elevator 46 to hopper 62 of box 55, beingdelivered from said box to the outside of main case 44 by elevator 49.The fans at the ends of each of said boxes circulate the air through theperforations of the walls as indicated by small arrows in Fig. 8, thusmaking a com plete circulation of air throughout the whole of the maincase 44. rlhis construction makes a better circulation of air, with lesspower than could be obtained if each of the smaller boxes had a separateand independent circulation of air therein, because the fans in thearrangement shown, combine their power, and the current moves through alarger cycle, and is less hindered in its circulation through theapparatus. 65 designates openings near the bottoni of the main case 44for admitting' air to the interior of the apparatus when assembledwithin said main case. 66 are dampers for controlling the entrance ofair through said openings 65. The ventilators, 19, protrude through thetop of the main case shown, but the ele vators 45 and 46, are confinedwithin said main case so that the material being dried is not exposed tothe outer atmosphere during its passage through the main case.

1t will be seen that an improved system of circulating air throughmaterial being dried results from assembling the troughs havingperforated sides one above the other and mounting transversefan-carrying shafts between said troughs, because the trough next aboveand next below each shaft receives practically as strong a current ofair as though the shaft and its fans were provided in combination with asingle trough only. By this invention., therefore, a plurality oftroughs are simultaneously sul jeeted to a current of air which would beexpended on a single trough if the drying apparatus were otherwiseconstructed. However, this invention is an improvement over otherdevices of its class in an important respect even when the fans are usedin connection with a single trough, for the reason that on account ofthe air being admitted transversely to the body of material in thetrough and the fans producing a transverse current of air against thetroughs simultaneously with the stirring of the material therein, a morecomplete aeration of the material being operated upon results than canbe obtained by any construction which merely passes the air over the topof the material.

By locating blowing fans 23 and 25 at dilferent points with respect tothe length of the troughs and mounting said fans in position to blow airtransversely through the perforated walls ofthe troughs, thus blowingthe air in reverse directions at different oints along the length of thetroughs, a circu ation of air is caused entirely within the case. Thisarrangement causes the air to take up as much moisture as possiblebefore escaping through ventilator 19 at the top ofthe apparatus.

lt is to be understood that, while 1 have described what 1 at presentconsider the best embodiment of the invention, 1 do not limit myself tothe exact construction shown, but may adopt various modifications withinthe scope of the claims 'without departing from the spirit of theinvention.

l claimt- 1. In drying apl aratus, in combination, a case forming a c'ying chamber, a trough therein having a curved perforated bottom, ashaft above said bottom, extending longitudinally thereof, stirringmeans carried by said shaft adapted to advance material along saidtrough, a semi cylindrical screen above said trough and inclosing saidstirring means, the lower portion of said screen resting upon the upperedge of said trough and means for rotating said shaft to move materialalong said trough.

2. In drying apparatus, a trough having walls perforated to allow air topass transversely through said trough, fans located at Y differentpoints with respect to the length of said trough, said fans beingadapted .to blow air transversely through said trough, and means forrotating said fans to direct currents of air through said trough inreverse directions.

3. In drying apparatus, a trough having a curved perforated bottom, ashaft over said trough extending lengthwise thereof, a series ofspirally-arranged radial flattened arms carried by said shaft, the endsof said arms being turned axially to an angle with relation to thelength of said trough, said arms being ranged around said shaft inadvance of each other to leave air spaces between t'he ends of saidarms, means for rotating said shaft, and means to cause a current of airto pass transversely through perforated bottom of said trough.

4. ln drying apparatus a trough having perforated sides to allow air topass transversely through the body of material in said trough, means forproducing a cu rent of air Yand directing the saine transversely againstsaid trough, stirring means for stirring the material in said trough andmeans for simultaneously operating said stirring Vmeans and said meansfor producing the air current.

5. In drying apparatus, a series of superposed approximately horizontaltroughs, feeding means to deliver material to one end of an uppertrough, discharge means at the other end of said trough to allowmaterial to be fed to asecond trough .there beneath, there being apluralit r of troughs beneath the upper trough having discharge openings'to provide for material being fed through the troughs in reversedirections, an elevator for raising material from the lower- Amosttrough of the series, another series of troughs likewise constructed toreceive material from said elevator, a separate case for each series oftroughs, means in each sepa- 'rate case for circulating air through thematerial in the troughs, a main case including both the first-mentionedcases and means for discharging material from the last set of troughs tothe outside of main ease.

6. In drying apparatus, a case, a succession of boxes within said case,means for.

therethrough.

7. In drying apparatus, a main case, a plurality of boxes within saidmain case, drying apparatus in each of said boxes, means for feedingmaterial to one of said boxes, means for progressively moving saidmaterial from said feeding means through all said boxes within the maincase, means for discharging the material from the last of said pluralityof boxes through which the material is passed, and means within each ofsaid boxes for creating a draft of air, said boxes having perforatedwalls to cause the current of air created by one of the boxes tocirculate through the other boxes.

'8. In drying apparatus a case, a plurality of superposed troughsmounted therein said troughs having perforated sides to allow air topass transversely through bodies `of material in said troughs, one lormore shafts between said troughs extending transversely thereto, fansmounted on said shafts, stirring means to stir the bodies of material insaid troughs and means for simultaneously operating said stirring meansand rotating said shafts to cause a current of air to pass transverselythrough said troughs.

9, n drying apparatus in combination a ease, a substantially horizontaltrough therein having perforated sides, means in said case near one endof said trough for producing a current of air and directing the sametransversely against one side .of said trough, means in said case nearthe other end of said trough for producing a current of air anddirecting the same against the other side of said trough, means forfeeding material to one end of said trough, and stirring means to stirmaterial 'in said trough and move the niaterial 'therealong In testimonywhereof have hereunto signed my .name in the presence of two subscribingwitnesses at Los Angeles, in the county o'f Los Angeles and State ofCalifornia, this 8th day of February 1908.

` ROBERT 'GRAUER lllitnesses ALBERT H. MERRILL, FLORA H. 'Foss

